An information processing system is configured such that various types of peripheral devices are connected to a personal computer or server, via, for example, a PCI (Peripheral Component Interconnect) bus.
It is conceivable to employ the DMA (Direct Memory Access) architecture for accessing a memory of the processor from a peripheral device in order to reduce the load of the processor. By doing this, areas to be used by peripheral devices are respectively allocated in a memory area of the processor, so that the peripheral devices can directly access the areas respectively allocated thereto.